默认设置ExecutionPolicy 命令尝试设置计算机范围值。你只需要你的C＃应用​​程序的范围内更改设置，所以你应该添加 -Scope过程选项添加到命令。

The default Set-ExecutionPolicy command attempts to set the machine-wide value. You only want to change the setting within the scope of your C# application, so you should add the -Scope Process option to the command.

使用获取帮助的Set-ExecutionPolicy -detailed 显示以下信息：

注：要更改执行策略默认（LOCALMACHINE）范围，启动Windows PowerShell使用以管理员身份运行选项

NOTE: To change the execution policy for the default (LocalMachine) scope, start Windows PowerShell with the "Run as administrator" option.

...它也描述了 -Scope 选项。

... and it also describes the -Scope option.

这具有的优势 仅 的影响的执行策略脚本从C＃应用程序中运行，它不会不必要地更改默认的PowerShell行为的执行策略。 （所以这是一个安全很多，特别是如果你可以让你的应用程序运行的脚本的有效性的保证。）

This has the advantage of only impacting the execution policy for scripts run from your C# application, and it doesn't unnecessarily change the execution policy for the default PowerShell behavior. (So it's a lot safer, especially if you can make guarantees about the validity of the scripts your application runs.)